


Conservation of Energy

by 221bdragonslayer



Series: Princess Diaries AU [2]
Category: Agents of S.H.I.E.L.D. (TV)
Genre: F/M, Princess Diaries AU, Some angst, but also fluff
Language: English
Status: Completed
Published: 2018-10-18
Updated: 2018-10-18
Packaged: 2019-07-25 22:36:13
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,382
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16207073
Author URL: https://archiveofourown.org/users/221bdragonslayer/pseuds/221bdragonslayer
Summary: "He should have known. A part of him had. Fitz was no longer that kid that Jemma had asked to the ball, but that kid’s fears were proving true. Of course it was all right for a teenaged princess to kiss him. But it was inevitable that an adult Jemma, ready to leave the relative fun and games of a princess behind and become a queen, would have different priorities when it came time to choose forever." A sequel to Heir to the Throne, loosely based (very, very loosely based) on Princess Diaries 2.





	Conservation of Energy

It was the night before Jemma’s wedding. She sat on the palace balcony, the starlight glittering off her ring whenever her hand shifted. It didn’t often; she was very still, not one part of her body fidgeting with nervous jitters.

Fitz’s eyes soaked in every detail of her, but he leaned against the walls in her room and just silently watched.  Although he tried to stop his thoughts from travelling to how she would look walking down the aisle tomorrow with white fabric swishing around her ankles with every step closer and her bright eyes focused on the love of her life, he couldn’t stop them.

No matter how much they hurt.

Genovian Parliament, citing tradition, dictated that Jemma had to be married, or the throne would go to the next closest heir. The aforementioned “next closest heir” would be young Werner Von Strucker, whose appearance made Fitz wonder just how many snakes could possibly pop out of the woodwork and try to steal the throne during Jemma’s lifetime.

He had never doubted Jemma’s ability to find a husband. In many ways, she had grown since their kiss after the ball. She understood political intrigue and subtlety, able to participate in it as the Jemma of high school who blushed at the slightest lie on her lips never would have. She possessed a deadly accuracy with a firearm, unwilling to leave her defense to her guards alone. But, she was still Jemma: Jemma, whose eyes still sparkled for science, who still loved a challenge, who still excelled at preparation and making lists for every duty.

As for Fitz,  he was still in love with her.

Correction: he was more in love with her.

That was why he had recognized that while it hurt, it was necessary for him to watch her sift through lists of bachelors and potential suitors with the the queen and Daisy Coulson, settling on one with a handsome face, a good title, and a flawless past. It was necessary for him to watch her accept flowers and dance with a perfectly respectable, perfectly dull man.

And now, it would be necessary for him to watch her flutter with nerves over having the perfect wedding and don a wedding gown for another man. To watch Jemma smile at him as she walked down an aisle, as she promised her love to him, as she kissed him in front of an altar.

It would be cruel to force her to give up her birthright for the sake of his jealousy. But, oh, tomorrow would hurt.

It already did.

 

* * *

 

 

He should have known. A part of him had. Fitz was no longer that kid that Jemma had asked to the ball, but that kid’s fears were proving true. Of course it was all right for a teenaged princess to kiss him. To invite him to spend his summer vacation at the palace in Genovia. To enjoy that glorious summer where not only did he help Jemma build her lab, but he improved the queen’s castle staff’s efficiency by over fifty percent with the gadgets he invented (the queen was ready to knight him), snuck copious amounts of snacks from the castle kitchen (which he always shared with Jemma), and persuaded Jemma to order a raised flower bed in her garden that looked like the Tardis (it didn’t take too much persuading). Of course it was right that he became a favorite and that it was all right to invite him back every holiday after.

But it was inevitable that an adult Jemma, ready to leave the relative fun and games of a princess behind and become a queen, would have different priorities when it came time to choose  _forever_. She would have to.

Fitz scolded himself for allowing himself to ever believe otherwise.

At first, when she had told him that she had to get married to keep the throne, he had hoped for a moment, a dizzy moment in which all the colors of the world were more vivid and all its lights more bright, that she was asking him. Then, the slump of her shoulders and the way she avoided his eyes bring his feet and his heart back to earth with a dull thud: it couldn’t be him.

The king of Genovia had to have a title and the political savvy to rule a country: common sense dictated the later, and tradition demanded them both.

Leopold Fitz had neither.

But Will Daniels did. He didn't understand her when she talked science or finish her sentences, of course, but they did make a nice looking couple. They certainly weren't soulmates by a long shot, but they could find pleasure in each other's company. It was a match that the press could fawn over and that no one could find fault with. 

Jemma, however, still clung to Fitz desperately. The way her fingers dug into his arm and the plea in her eyes as she first told him about Will bellied that she could not bear to lose him again. So, they agreed to remain best friends and shook on it. He still came to the palace: they still worked in the lab, watched Doctor Who together, and finished each other’s sentences. They had been friends before they had been... _something more_ , and even then they had still been best friends. Now that was all they had left.  

Most days, Fitz didn’t know if this was a comfort or only created more pain. It meant witnessing Will and Jemma sharing smiles tinted with soft affection, seeing her easily, naturally bump her hip against his while she teased him, and--in one supremely awkward moment when he walked around a corner--learning that Jemma knew just how to draw that last little bit of enjoyment from Will's lips. It made him long for the days when the sweetness of each of those gestures and those looks had been for him. He wasn’t sure that this was easier for Jemma either, not when she sat on her hands in the lab as if they itched to brush an unruly curl back from his face or when she hesitated to give Will a quick peck on the lips because her eyes were flickering automatically to Fitz--reflecting hurt in their chestnut depths because she knew watching hurt him.

It was obvious that she was confused.

Fitz was confused.

Will--with the way his brows drew together and his gaze hopped back and forth from Jemma to Fitz whenever the three of them were in the same room, analyzing their interactions-- was confused.

If they all weren't so lost, it might have been funny; as they were all thinking themselves in circles, it was a mess and anything  _but_  humorous.

But Fitz knew one thing. If all he could be to Jemma Simmons was a best friend, then he darn well was going to consider himself lucky to be even that. In that, he could say without question, Jemma felt the same.

 

* * *

 

 

He stood now in the shadows, studying the way the starlight cast a dim glow around the lines of her figure on her wedding night, and his heart ached. She was so beautiful, his Jemma.

No, not his.

 _Will’s_ Jemma.

“Fitz.”

He started, guiltily. Jemma hadn’t even turned, but he didn’t question that she could recognize his tread, nearly silent as it had been.

They do know each other inside and out, after all.

“Uh, where’s Will?” Fitz stammered. “With the big day tomorrow, I, um, thought he would be here with you.”

Jemma just shook her head, her chest heaving with a sigh. “There won’t be a big day tomorrow.”

And suddenly, Fitz wasn’t sad anymore. By all rights, he should have been rejoicing because Will had been his rival, but that didn't even occur to him.

No, he was  _furious_.

He all but stomped out onto the balcony, hands clenched into fists. He forced himself to relax his hands, but his fingers just came to land indignantly on his hips instead. How dare Will not recognize the treasure in front of him? How dare Will deny Jemma this chance to take the throne that she had worked so hard to make herself worthy of (even though Fitz had known she was worthy all along)?  _How dare he?_

He only realized that he had voiced those last three words aloud when Jemma finally tilted her head just enough to give him an amused smile.

“It’s all right, Fitz.”

“No,” he fumed. “It isn’t! You’ve worked so hard for this, and he can’t just--”

“Fitz!” She was toying with the ring on her finger, but he didn’t notice.

“Well, he never deserved you, Jemma! He could never--”

“Fitz.” That was a queenly voice that sounded supremely like her grandmother, a voice that could command the attention of a nation, and he obediently let the words die on his tongue.

“Our feelings were mutual; we didn’t part on bad terms. We just agreed that, however ideal of a match we might be, we didn’t have a…” Jemma paused to consider her words. “...A spark,” she finally decided.

 He felt his brows knit together in confusion. It was so Jemma, so congruent with the very core of her being, to think for herself. But it was antithetical to everything he had ever known of Jemma to refuse a duty despite personal sacrifice, especially one that was made for Genovia. Ever since the fateful Independence Day Ball, her country and her position have become part of her. By all rights, if she didn’t sound more disturbed that she was losing a fiance, she should sound more disturbed that she was losing her throne.

 She shouldn’t have to choose between her heart--marrying a man she doesn’t love-- and her country. Fitz longed to take that choice away from her--but did he understand her heart?

It was possible that she wouldn’t want him anymore than she wanted Will.

That thought hurt, but he had to force himself to consider it. His fingers nervously curled into his palm, the nails biting into his skin as the doubts grew louder and louder inside his skull.

There was also the fact that, did she want him, he would have to become king. He would have to accept the duties of king-- the stifling polite talk, political intrigue that tied his brain in knots, public speeches given in the hot spotlight of the press. It sounded like a nightmare, but he would do it for Jemma. He would do anything for Jemma, really, and that answered the question. Anything included potentially making a fool out of himself by proposing a marriage that she might refuse.

He took a step closer to her, and he realized for the first time that the ring he spotted on her finger wasn’t Will’s engagement ring. It was one that he made for her, for her twentieth birthday.

Somehow, the sight gave him courage.

He wished that he could have planned this out properly. For goodness sake, he didn’t even have a ring or a perfect speech that he had spent hours on, selecting and trying words until he found the ones that fit together as flawlessly as pieces in a puzzle. But her country was at stake, and he loved her too much to watch her lose something that matters so much.

“Jemma,” he stammered, and he belatedly dropped down on his knees because some part of this needed to be done right. “Jemma, will you marry me?”

She started, her foot thumping against the legs of her chair. The glow of the moonlight illuminated her wide eyes, making her look rather like an owl. It would have made him chuckle, if his heart hadn’t been thumping so violently against his chest. “Fitz…” she laughed, the sound fragile. “Are you...are you doing this so I can rule Genovia?”

No. He was doing this because he loved her: her smiles, her words that bubbled with excitement, the way that the curves of her body settled so comfortably into his when she needed his closeness and comfort. Because he wanted to spend the rest of his life with her.

But his heart sank at the question, at the tone that suggested that the thought of him marrying her for any other reason than kindness has never even popped into her mind. So Fitz murmured, “Yes.”

To his horror, the light in her eyes dimmed. She turned away from him, and her voice sounded choked when she eventually answered. “I couldn’t ask that, Fitz. I...I don’t want you to make that sacrifice.”

He had misread her, badly. Fitz could understand her in practically every other way, but somehow they always ran into a brick wall between them when it came to matters of the heart.

He really was mucking this up.

Before they were even fully thoughts, he found that they were words slipping vehemently off his tongue. “Marrying you could never be a sacrifice.”

He twisted his fingers around the fist formed by his other hand, too nervous to hold them still at his sides. “It would be a pleasure to spend the rest of my life with you,” he said, simply. “I love you, Jemma.”

Her chair creaked as she turned to study him, climbing up onto her knees so she could study his face. Her eyes traced every line, seeing every nuance, and he allowed her to read the honesty there. And gosh, but the dark, liquidy cocoa of her eyes was beautiful. It arrested his gaze, and somehow nothing else mattered because he was losing himself in them. And being lost in her was such a familiar, such a comfortable place to be.

“And I love you,” she whispered, pressing the words against his lips. His hands slid down, exploring the curve of her waist, and then drew her close.

When the two of them parted, slightly breathless but without breathing their gaze, his lips turned up in a mock pout.

“You never answered me, Simmons.”

“Excuse me? Is that how you address royalty?” she asked, her indignance no more genuine than his pout.

“All right, then. Princess Jemma Mignonette Grimaldi Simmons Renaldo of Genovia, will you marry me?”

Her fingers traced the line of his shoulder, coming to rest on the back of his neck and leaving a tingle in their wake, in every centimeter of skin she touched. Her warm breath whispered over his cheeks. Then, her lips curved up in a grin.

“No.”

 

* * *

 

 

“I’m not sure if I’m ready for this,” he groaned the following day.

“For marrying me?” Jemma asked from where she lay against his side. Her tone was light with teasing, almost as light as the lazy way her fingers traced the lines of his arm up to his shoulder and back to his wrist again, but the way she avoided his eyes belied an undercurrent of seriousness running through the words.

Of course he was ready. He had been for years. How could she ever question that? “Of course not,” he said, allowing his tone to show just how absurd he found her question. Her lips twitched into a smile against his chest. After pressing a kiss against the top of her head, Fitz stopped her fingers in their path over his skin and squeezed them gently.

“Then what?” she asked.

“To be royalty.”

“Well, you don’t have too much cause for worry, Fitz. Based on Parliament’s decision today, you’re just a prince consort. I've got all the hard work.”

Given that he never wanted the throne, he wanted  _Jemma_ , the fact that  _she_ would rule was infinitely consoling. He felt warmth bloom in his chest, pride for what Jemma has accomplished. He would never, ever forget the applause earlier that day or the way that the members of Parliament, one by one, stood up after her eloquent speech and added their votes to abolish the foolish marriage tradition. That was his Jemma: strong in her convictions in a way that made others want to be strong, too. She had said that a queen could rule without a king, thank you very much, and now those were the words on everyone’s lips.

“That doesn’t mean,” she had told him last night, however, with her eyes bright, “that the queen  _wants_ to rule without a husband.”

Pressing her lips against his again, she had told him in no uncertain terms that Jemma Mignonette Grimaldi Simmons Renaldo did not. She wanted him.

Nonetheless, that “no” had given him a scare that he hadn’t quite forgiven her for, even after she had explained that the “no” was only until she could make a point.

Now, Fitz allowed his cheeks to crinkle into a smug smile against the warmth of her hair. “Yes, and good thing that’s all I am. While the  _queen_ has to sit and listen to political squabbles, the  _prince consort_ can tune it all out and consider the applications of that new material that can shape shift in response to stimuli like light and--”

His words broke off in a yelp as the soon-to-be queen punched his arm with royal dignity.

With a satisfied smirk, she dropped back into his lap. A moment later, her voice drifted back up to him on the breeze.

“Don’t you wonder, Fitz?”

“Wonder what?”

“What happened between me and Will.”

“You said there wasn’t a spark.” That had been good enough for him; he didn’t want to dig at a sore if their break-up was a painful memory. But if she wanted to talk about it, he would listen.

“Yes,” Jemma said, then paused thoughtfully. “But there was more to it than that.”

“Oh?”

“Mm-hm. The reason I knew there wasn’t a spark was because I knew what a spark felt like, and I knew that wasn’t it.” The information in that sentence was frankly rather obvious, so he didn’t realize why she had voiced it until she poked his arm gently. “I knew from you, Fitz.”

The warmth in her voice made the tips of his fingers, tangled in her hair, tingle. How many people had been allowed a happy ending like this, had been allowed to have a partner so tightly linked to them heart, mind, and soul, had been allowed to have and to hold that partner?

Jemma’s thoughts were apparently travelling the same path.“Will saw the spark between us, too,” she said, twining her fingers into a fistful of his shirt’s fabric. “He said he hoped that he could find what I had with you himself someday.”

He recognized the guilt in her tone. “Did you...did you love him?” he asked, afraid to hear the answer but knowing he needed to.

She was silent for a few moments, then he felt her head nod against his legs. “I did care for him. Because he was such a proper choice for a ruler of Genovia, and he  _was_ kind to me.” She held her breath as if expecting a vehement response from him, then she exhaled when none came. “But I loved you more, Fitz,” she whispered. “I always did. And when it came down to a choice between him and you, well...there wasn’t any choice at all.”

At that, overwhelmed by how  _blessed_ he was by this woman lying on his lap, he leaned down to press a gentle kiss against her forehead.

“Thank you,” he murmured. “Thank you for choosing me.”

She laughed, the sound light, and his heart warmed as it always did at the way her eyes crinkled when she laughed. “But it’s just Newton’s Third Law, Fitz. For every time I’ve chosen you, there’s one where you’ve chosen me.”

“But your reaction isn’t opposite. I think it’s more the Law of Conservation of energy.”

“Energy is neither created nor destroyed?” She paused to consider that, eyes narrowing as she tried to puzzle out the pattern of his thoughts.

“Yes.  The choice to love...it’s transferred from one of us to the other. And back again, like energy.”

She smiled now in satisfaction, understanding. “I like that. It’s something that belongs to both of us. And I like its implications.”

_It cannot be destroyed._

Fitz did, too.

**Author's Note:**

> I originally set out writing an epilogue to Heir to the Throne, but it seemed to take on far more narrative than I had planned and demand a whole oneshot of its own. Alas, what could I do but obey?
> 
> In all honesty, though, this oneshot was a lot of fun. Heir to the Throne Jemma reminds me a lot of young, naive, bubbly Jemma who didn't even pass her field exam from the first season of AOS. This Jemma, more mature with a few more years on her shoulders and a lot more experience and training in being royalty, is more like the capable Jemma of later AOS seasons. So it was a great opportunity for me to be able to write Jemma in different stages of her life and provide a parallel to that same journey in canon. Shame on both the AOS writers and on me that in both canon and this AU, she and Fitz face so many obstacles in their love for each other in both stages. As always, thank you so, so much for taking the time to read this!


End file.
